In recent years, electronic devices such as a tablet type laptop computer and a mobile information terminal have come to incorporate a touch panel in order to improve the operability and usability. On a touch panel, positional information on a display surface of a display panel can be input with a touch of a finger, a stylus pen, or the like. Thus, an intuitive operation by, for example, the user's direct touching on an image displayed in the display panel is possible. One known example of the display panel including the touch panel as described above is disclosed in Patent Document 1 shown below.
In a display device according to Patent Document 1, a touch sensor electrode for detecting a position is formed by arranging a plurality of meshed metal thin lines with a belt-like shape. Specifically, the touch sensor electrode includes a plurality of sensing electrodes formed of a belt-like shaped metal thin line disposed on a front side of a transparent substrate, and a plurality of driving electrodes formed of a belt-like shaped metal thin line disposed on a back side thereof. By detecting the difference in electrostatic capacitance between the sensing electrodes and the driving electrodes, the touch sensor electrode detects whether the touch has been performed. This display device includes the plurality of belt-like shaped sensing electrodes disposed with a space from the adjacent sensing electrode, and includes a dummy electrode in the space in order to solve the difference in visibility between the sensing electrode and the space.